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Abstract  

A new convenient method has been proposed to synthesize mixed-ligand -diketonato Tc(III) complexes, using the ligand exchange reaction [Tc(acac)2(CH3CN)2]++L [Tc(acac)2L]+ +2CH3CN where L is bza, dpm or dbm. The yield was about 30–40%. UV-visible and IR spectra of these complexes were measured. Characteristic features of the compounds were compared with those of the corresponding complexes of ruthenium.

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Abstract  

We prove that the centered three-dimensional Wiener sausage can be strongly approximated by a one-dimensional Brownian motion running at a suitable time clock. The strong approximation gives all possible laws of iterated logarithm as well as the convergence in law in terms of process for the normalized Wiener sausage. The proof relies on Le Gall [10]șs fine L 2-norm estimates between the Wiener sausage and the Brownian intersection local times.

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Abstract  

All complexes of the series [MO2L2]+ (M=Tc, Re; L=ethylenediamine (en), 1,3-diaminopropane (1,3-dap)) have been synthesized and their chemical reactivities investigated. The following properties were studied: stability of the aqueous solutions at different pH values, substitution kinetics, lipophilicity and protein binding. The complexes show very similar reactivity in aqueous solution. From a radiopharmaceutical point of view, no significant difference in their in vivo behavior is expected.

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Abstract  

When is the composition of paraproducts bounded? This is an important, and difficult question. We consider randomized variants of this question, finding nonclassical characterizations. For dyadic interval I, let h I = h I 0 be the L 2-normalized Haar function adapted to I, the superscript 0 denoting that it has integral zero. Set h I 1 = |h I|, the superscript 1 denoting a nonzero integral. A (classical dyadic) paraproduct with symbol b is one of the operators article image. Here, ɛ, δ ∈ {0, 1}, with one of the two being zero and the other one. We characterize when certain randomized compositions B(b, B(β, ·)) are bounded operators on L 2(ℝ), permitting in particular both paraproducts to be unbounded.

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Hydroxylamine derivatives in Purex Process

I. Study on the kinetics of redox reaction between N,N-diethylhydroxylamine and nitrous acid

Journal of Radioanalytical and Nuclear Chemistry
Authors: Zhang Anyun, Hu Jingxin, Zhang Xianye, and Wang Fangding

Abstract  

The kinetics of oxidation-reduction reaction between N,N-diethylhydroxylamine (DEHAN) and nitrous acid in nitric acid solution have been studied by spectrophotometry at 9.5°C. The rate equation is −d[HNO2]/dt=K[HNO2]·[DEHAN][HNO3] and the rate constantK=12.81 (mol/l)−2·min−1. A possible mechanism has been suggested on the basis of chemical analysis and Raman spectra. The activation energyE and the thermodynamic functions ΔH #, ΔG # and ΔS # are also calculated.

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Abstract  

The investigations concerning the thermal behaviour of a series of Ni(II) and Cu(II) complexes of type [NiLCl2mH2O ((1) L:L1, m=6; (3) L:L2, m=4) or [CuLCl]nCln·mnH2O ((2) L:L1, m=6; (4) L:L2, m=4) are presented. The ligands L(1) and L(2) have been synthesised by template condensation of 3,6-diazaoctane-1,8-diamine or 1,2-diaminoethane with formaldehyde and 2-amino-4H-1,2,4-triazole. The bonding and stereochemistry of the complexes have been characterised by IR, electronic and magnetic studies at room temperature. The in vitro qualitative and quantitative antimicrobial activity assays showed that the complexes exhibited variable antimicrobial activity against planktonic as well as biofilm embedded Gram-negative, Gram-positive and fungal strains. The thermal behaviour provided confirmation of the complexes composition as well as the number and nature of water molecules and the intervals of thermal stability.

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Abstract  

Mn(II), Co(II), Ni(II) and Cu(II) complexes having the general composition M(L)2X2 [where L = 2-pyridinecarboxaldehyde semicarbazone, M = Mn(II), Co(II), Ni(II) and Cu(II), X = Cl and NO3 ] have been synthesized. All the synthesized compounds were identified and confirmed by elemental analysis, molar conductance, magnetic susceptibility measurements, mass, IR, EPR, electronic spectral studies and thermogravimetric analysis (TG). The Molar conductance measurements of the complexes lie in the range 209–228 Ω1 cm−1 mol−1 indicating that the complexes are 1:2 electrolytic in nature. Thus the complexes may be formulated as [M(L)2]X2. The magnetic moment measurements of the complexes indicate that all the complexes are in high-spin state. On the basis of spectral studies an octahedral geometry has been assigned for Mn(II), Co(II) and Ni(II) complexes whereas tetragonal geometry for Cu(II) complexes. The thermal studies suggested that the complexes are more stable compared with free ligand. This fact was supported by calculating the thermodynamic parameters by using Horowitz–Metzger (HM) and Coats–Redfern (CR) equations. The free ligand and its metal complexes were also evaluated against the growth of phytopathogenic fungi and bacteria in vitro.

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Abstract  

New mixed-ligand complexes with empirical formulae M(4-bpy)L21.5H2O (M(II)=Mn, Co), Ni(4-bpy)2L2 and Cu(4-bpy) L2H2O (where: 4-bpy=4,4'-bipyridine, L=CC L2HCOO-) have been isolated in pure state. The complexes have been characterized by elemental analysis, ir spectroscopy, conductivity (in methanol, dimethylformamide and dimethylsulfoxide solutions) and magnetic and x-ray diffraction measurements. The Mn(II) and Co(II) complexes are isostructural. The way of metal-ligand coordinations discussed. the ir spectra suggest that the carboxylate groups are bonded with metal(II) in the same way (Ni, Cu) or in different way (Mn, Co). The solubility in water is in the order of 19.4010-31.8810-3ł mol dm-3ł. During heating the hydrate complexes lose all water in one step. The anhydrous complexes decompose to oxides via several intermediate compounds. A coupled TG-MS system was used to analyse the principal volatile products of obtained complexes. The principal volatile products of thermal decomposition of complexes in air are: H2O2 +, CO2 +, HCl+, Cl2 +, NO+ and other.

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Acta Botanica Hungarica
Authors: C. Çi̇rak, M. Odabaş, A. Ayan, B. Sağlam, and K. Kevseroğlu

The genus Hypericum has attracted scientific interest for recent years, since it is a source of a variety of compounds including hypericin. The present study was conducted out to develop leaf area prediction models for some Hypericum species containing hypericin, namely H. pruinatum, H. perfoliatum, H. aviculariifolium subsp. depilatum var. depilatum (endemic), H. montanum, H. montbretii, H. linarioides, H. triquetrifolium, H. bithynicum and H. perforatum growing wild in Northern Turkey. Lamina width, length and leaf area were measured without destroying to develop the models. The actual leaf areas of the plants were measured by Placom digital planimeter, and multiple regression analysis with Excel 7.0 computer package program was performed for the plants separately. The produced leaf area prediction models in the present study were formulised as LA = (a) + (b 1 × L) + [b 2 × (L × W)] + (b 3 × L 2 ) + (b 4 × W 2 ) + [b 5 × (L × W 2 ] + [b 6 × (L 2 × W)] + [b 7 × (L 2 + W 2 )] where LA is leaf area, Wis leaf width, L is leaf length and a, b 1 , b 2 , b 3 , b 4 , b 5 , b 6 , and b 7 are coefficients. R 2 values varied with species from 0.80 in H. aviculariifolium subsp. depilatum var. depilatum to 0.97 in H. pruinatum . All R 2 values and standard errors were found to be significant at the p < 0.001 level.

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Abstract  

Let G denote a locally compact abelian group and H a separable Hilbert space. Let L p(G, H), 1 ≤ p < ∞, be the space of H-valued measurable functions which are in the usual L p space. Motivated by the work of Helgason [1], Figa-Talamanca [11] and Bachelis [2, 3], we have defined the derived space of the Banach space L p(G, H) and have studied its properties. Similar to the scalar case, we prove that if G is a noncompact, locally compact abelian group, then L p 0(G, H) = {0} holds for 1 ≤ p < 2. Let G be a compact abelian group and Γ be its dual group. Let S p(G, H) be the L 1(G) Banach module of functions in L p(G, H) having unconditionally convergent Fourier series in L p-norm. We show that S p(G, H) coincides with the derived space L p 0(G, H), as in the scalar valued case. We also show that if G is compact and abelian, then L p 0(G, H) = L 2(G, H) holds for 1 ≤ p ≤ 2. Thus, if FL p(G, H), 1 ≤ p < 2 and F has an unconditionally convergent Fourier series in L p-norm, then FL 2(G, H). Let Ω be the set of all functions on Γ taking only the values 1, −1 and Ω* be the set of all complex-valued functions on Γ having absolute value 1. As an application of the derived space L p 0(G, H), we prove the following main result of this paper. Let G be a compact abelian group and F be an H-valued function on the dual group Γ such that

\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\sum \omega (\gamma )F(\gamma )\gamma$$ \end{document}
is a Fourier-Stieltjes series of some measure µ ∈ M(G, H) for every scalar function ω such that |ω(γ)| = 1. Then Fl 2(Γ, H).

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